Luminous tube sign letter



Aug. 16, 1932. w. P. DRURY LUMINOUS TUBE SIGN LETTER Filed April 26.1930 /NVEN TOR Patented Aug. 16, 1932 WILLIAM. PAUL DRURY, OF LOSANGELES,

UNITED STATES PATENT OFFICE -CALIFORNIA, AS SIGNOR OF ONE-HALF TO FREDHOTGHNER, OF LOS ANGELES, CALIFORNIA LUMINOUS TUBE SIGN LETTERApplication filed April 26,

tubes on signs was to secure them by insulators at a distance of fromone half inch to two inches from the nearest metal. The electrodeterminals turn backward and enter the sign thru glass or porcelainbushings. Due,

to the high voltage used and the liberal clearances that necessarilymust be provided because of inaccuracies in manufacture, quite large andunsightly bushings are used. The entire make up of such devices isawkward in the extreme, the tubes are liable to breakage from manyinfluences and the cost of shipping is excessively high.

The necessity of allowing insulating clearances and the various otherlimitations inherent in the type of construction has also prevented theuse of channels on the letters as was customary in the prior art,incandescentlamp signs. For that reason considerable light is cast uponthe body of the sign. This is objectionable as it detracts from thereadability of the letters. Dust, rain, fog or snow in the atmospherealso contribute to reducing the readability by becoming illuminated bythe light passing to the sides of the letters.

In the present invention due to the insulating quality of the letteritself, the tube may be mounted directly in contact with the letter.Thus the insulators for supporting the tube away from the letter aredisposed of and the letter itself being provided with openings for theelectrode terminals, the insulating bushings are eliminated. The tubemay be recessed into the letter as in. the preferred form of theinvention illustrated, thus prelventing any light from reaching the bodyof the sign and also overcoming almost com- 1930. Serial No. 447,580.

pletely the halation effects in the atmosphere around the letter.However, as it is desirable that the letters have an illuminated strokeof a width equeal to that customary with the prior devices, I accomplishthis end without the necessity of positioning the tube a distance fromthe face of the letter. I have found that if a letter be made of glasshaving the optical characteristics of white or opal glass and the tubebe set into a recess formed from the surface of the letter back into thebody thereof, the letter will be illuminated in a very satisfactorymanner by light transmitted thru the body of the glass directly from thetube and scattered from innumerable points within the glass.

Thus the tube and letter alone are illumihated and all light is cut offfrom reaching the body of the sign. The effect of this device isparticularly attractive and has strong advantages over the opticaleffect of the prior devices. It is to be noted that light reflected froma painted surface is brightest at certain angles depending on the degreeof luster that the surface has. These angles are usually those out ofthe .range of ordinary view and thus considerable light is lost.However, if the surface be painted with a dull finish it becomes coatedwith dirt in a short time. In the instant invention this is overcome asthe redirecting of the rays of light takes place within the body'of thelass and produces an attractive, soft and uni orm glow that neverchanges.

Further advantages are secured in this invention in providing a unitwhich can be shipped with facility and without danger, one whichprovides protection for the tube when mounted in the sign from thevarious influences tending to break the tubes, such as hail stones,frost, etc., and one which is a complete electrical unit withoutadditional insulating means.

Other objects of the invention will be ap- I according to this inventionshowing a discharge tube in position and a portion of the body of thesign in which the device is illustrated as mounted.

Figure 2 is a sectional View of the letter shown in Figure 1 taken onthe line 2-2, Fi ure 1.

igure 3 is a. cross section of a stroke of the letter shown in Figure 1taken on the line 3-3, Figure 1.

Figure 4 is a cross section of a modified form of this invention toillustrate a letter formed from a moulded mass of glass.

Figure 5 is a sectional view of a portion of the letter shown in Figure1 taken on the line 4-4, Figure 1.

In the drawing, numeral 1 indicates a letter made according to thisinvention, having the plate 2, from which are pressed the strokes 3, 4and 5 comprising the strokes of the letter A. Into the strokes arepressed the grooves 6, 7 and 8 which are intercommunicating and form thecharacter recess into which the discharge tube 9 is positioned. Thegroove 7 is recessed deeper than the 'others to allow the return bendportion 10 of the cross stroke of the letter to set in deeper than theother portions of the tube thus providing for the center of the tubeproper falling in the plane 11 of the face of the strokes. One half ofthe tube is thus sheltered from rain, hail stones, etc., the exposedportion being convex easily sheds water and offers no lodgement to hailstones.

It is not desired however that the letter contact directly with theglass but it should have a small clearance to allow for irregularitiesin manufacture. Thus the tube is supported by the clips 13, 13, etc.,which support it in a flexible manner and a slight distance from anysurface of the glass leaving a space indicated by numeral 12 in thevarious views around the tube. Any suitablet e of clip may be used but Irefer to use a at spring bent into suitable s ape and passed thru anelongated opening pressed thru the plate as indicated at 14 and held bya cotter pin 15, Figure 3. An alternative type of clip is shown inFigure 4.

Now it is to be observed that the tube is so positioned that no rays oflight can reach the background of the sign which in Figure 1 wouldcorrespond to the sheet of metal indicated by 16. If desired the edgesof. the raised strokes may be painted but this is not necessary as theamount of light that will be radiated from the edges toward thebackground is too small to be a factor. The form of the letters are cutfrom the background and the letters are secured thereto by bolts asindicated by 30, 30, etc., passing thru holes' 31, 31, etc., in theletter plates. It is also to be observed that an appreciable proportionof the light emitted by the tube is transmitted into the edge of theglass and thus of the tube.

illuminates the stroke of the letter by virtue of that portion of theradiation that is reflected back towards the sign in the prior devices.

While I prefer to sheet of glass, a satis actory letter may also beformed by moulding a solid block of glass as shown in Figure 4. In thisview, 17 indicates the letter plate proper; 18, the raised stroke; 19,the groove for the tube; 20, the clip for supporting the tube; 21, thetube; and 23, the opening thru the glass for the clip.

In Figure 5 I illustrate the manner of forming the terminal openingsfor-the ends The material of the plate is pressed back as at 24 leavingan opening 25 thru which the electrode terminal 26 of the tube extends.Any suitable electric connection may be used inside of the sign tosupply current to the tube. It is here to be noted that the glass plateitself takes the place of the customary porcelain bushing, and whereasin the prior devices the bushing presents an awkward element in thesign, this terminal is entirely concealed.

It is to be understood that this letter may be mounted in any desiredfashion into an electric sign as this invention is not limited to anyparticular type of mounting. By way of suggestion three types ofconstruction are here set forth making use of this invention:

First, the entire plate as shown in Figure 1 with the tube mounted maybe assembled in a frame with other letters, dispensing with thebackground.

Second, the letters may be mounted into a sign face as shown in Figure 1with the background cut out to the form of the letter, only the gaisedportion with the-tube being expose Third, the letters may be madewithout the plate, that is in skeleton form, and bolted ress the letterfrom aonto the front of the background, holes being is .thus to belimited only by the following claims.

What I claim is: 1. In an electric sign, a sheet metal background, anopening thru said background having the form of a. character, a body ofdielectric material closing said opening and having a tube light in thegeneral 'form of said character secured thereto and out of contact withsaid background, said tube light having a pair of terminals extendingbackward into suitable depressions in said body of dielectric materialand means on the back of said body to make contact with said terminals.

2. In an electric sign, a sheet metal background having an opening inthe general form of a character, a body of dielectric material having araised portion in the general form of said character said raised portionextending thru said opening, adepression in the face of said raisedportion having the general form of said character and a tubular lightpositioned in said depression in said raised portion.

3. In an electric sign, a sheet metal background having an opening inthe general form of a character, a body of dielectric material having araised portion in the general form of said character said raised portionextending thru said opening, a depression in the face of said raisedportion in the general form of said character, there being a pair ofopenings thru said body terminating in said depression, and a tubularlight in the general form of said character, formed to fit saiddepression and positioned therein said light having two terminalsdisposed to pass thru said openings.

4. In an electric sign, a luminous character including a body of glasshaving a depression in which is disposed a luminous tube light, saidlight having the general form of a character at least one stroke ofwhich is doubled back under itself the character in general beingrepresented by strokes of tubing that lie in a single plane, saiddepression being of varying depth and of such values that in thoseportions of the character represented by a single stroke of tubing thedepression just allows the tube to become partly concealed in saiddepression and in that stroke in which the tubing is doubled underitself the depression allows the doubled under portion of the tubing tobe completely concealed and the other portion to be partly concealed bythe walls of the depression.

5. In an electric sign, a sheet metal background, an opening thru saidbackground having the general form of a character, a body of dielectricmaterial having a raised portion also in the form of said character andextending thru said opening, there being a pair of openings thru saidbody for the reception of the terminals of a tube light and additionalopenings thru said body'f r the reception of fastening means to secure atube light thereto, and a tube light also in the general form of saidcharacter secured to said raised portion by suitable fastening meanspassing thru the last said openings and having a pair of terminalsextending thru the first said openings, said tube light bein wholly outof contact with said backgroun 6. In an electric sign, an opaquebackground having an opening in the general rm of a character, a body ofdielectric materlal having a raised portion in the general ture.

WILLIAM PAUL DRURY.

